RCC1 is the only known exchange factor for the Ran guanosine triphosphatase and performs essential roles in nuclear transport, spindle organization, and nuclear envelope formation. RCC1 binds to chromatin through a bimodal attachment to DNA and histones, and defects in binding cause chromosome missegregation. Chromatin binding is enhanced by apo-Ran. However, the mechanism underlying this regulation has been unclear. We now demonstrate that the N-terminal tail of RCC1 is essential for association with DNA but inhibits histone binding. Apo-Ran significantly promotes RCC1 binding to both DNA and histones, and these effects are tail mediated. Using a fluorescence resonance energy transfer biosensor, we detect conformational changes in the tail of RCC1 coupled to the two binding modes and in response to interactions with Ran and importin-alpha. The biosensor also reports changes accompanying mitosis in living cells. We propose that Ran induces an allosteric conformational switch in the tail that exposes the histone-binding surface on RCC1 and facilitates association of the positively charged tail with DNA.
Pubmed ID: 18762580 RIS Download
Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.
A contract research organization providing drug development and animal testing services. Under the name Covance Research Products Inc., based in Denver, Pennsylvania, the company also deals in the import, breeding and sale of laboratory animals. It breeds dogs, rabbits, guinea pigs, non-human primates, and pigs, and runs the largest non-human primate laboratory in Germany. (Wikipedia)
View all literature mentionsCell line HEK293T is a Transformed cell line with a species of origin Homo sapiens (Human)
View all literature mentionsCell line MDCK is a Spontaneously immortalized cell line with a species of origin Canis lupus familiaris
View all literature mentions